Variable geometry thrust vectoning means for a gas turbine

Abstract: Orientable axisymmetric nozzle of variable geometry for gas turbine propulsors which comprises convergent (2) and divergent (3) sections formed by master petals (4, 5) and slave petals (33, 34) duly connected together, each divergent master petal (5) being connected to an outer annular control part (6) by a biarticulated bar (15). This bar is connected by one end to the part (6) by a cylindrical articulation (16) while by its opposite end it is connected to the divergent master petal (5) via intermediate bars (26, 27).

Description: The present invention refers to a convergent-divergent nozzle of variable geometry capable of orienting the flow of gas, for a gas turbine propulsor, used as means of propulsion in aviation. More specifically, in a preferred application, the nozzle to which the present invention relates is of the axisymmetric type, comprising a convergent zone followed, in the direction of flow, by a divergent zone, both formed by master petals, distributed circumferentially around the longitudinal axis of the propulsor and connected to each other by articulations, and by slave petals, also connected together by articulations and distributed circumferentially around the longitudinal axis of the propulsor, the convergent zone of which defines an A8 throat of variable area and the divergent zone of which, also of variable geometry, may be actuated so as to orient the flow of gas, and therefore the thrust, in any direction on a cone directed around the longitudinal axis of the propulsor. The maneuverability of airplanes is an essential factor. This maneuverability, which has been obtained up to now by aerodynamic forces, can be substantially improved by changing the orientation of the flow from its normal axial direction of actuation. The orienting of the flow of gas has been used for many years in rocket motors. In them, the systems are much simpler, since the nozzles are of constant geometry. Convergent-divergent nozzles of variable geometry are of relatively recent introduction in supersonic planes driven by turbojet or turboprop propulsors. In this class of nozzle, the systems for the orienting of the flow are not yet in operational stage, being in the experimentation or development phase. The ones which are in the most advanced state are those of the two-dimensional type in which the flow is oriented only in one plane. It is of particular advantage to effect the orientation of the flow in nozzles with axial symmetry since the direction of the flow can then be varied in any axial plane, the pitch and yaw planes being particularly important. There are various patents covering mechanisms for orienting the flow in this type of nozzle, since theoretically it is possible to effect this in different ways, although it is very difficult to see to it that they are not of a high degree of complication. To orient only the divergent zone of the nozzle downstream of the A8 throat area has the advantage that the disturbances induced by the orientation are not transmitted upstream of the propulsor and that the sealing of the spaces between the different moving parts is simplified. Even thus, there remains the problem of the seal between divergent master petals during the orienting of the flow. With regard to this, reference should be made to US Patent Application 336369 of 1989 (US A-4994660) and to Spanish Application No. 9200369 of 1992, corresponding to the european application EP-A- 557229, which set forth different embodiments of nozzles in which only the divergent zone, or a part of it respectively, is oriented. In order to solve the sealing of the spaces between divergent master petals there are various solutions, such as those contained in US Patent Applications 804021 of 1985 (US-A-4690330), 804022 of 1985 (US-A-4662566), 336380 of 1989 and 07475465 of 1991, and Spanish Applications Nos. 9200369 of 1992, 9202157 of 1992, and No. 9301991 of 1993. In Spanish Patent Application No. 9200369 of 1992 (EP-A-557229) an orientable axisymmetric nozzle of variable geometry for gas turbine propulsors is claimed. Said nozzle consists of a convergent zone and a divergent zone, both formed of master petals and slave petals distributed circumferentially around the longitudinal axis of the propulsor, and it includes control and outer radial support means for regulating the throat area and control means for regulating the orientation of the flow, it being characterized by the fact that the variation of the A8 throat area and the orientation of the flow are effected by a single control system. This single control system is formed of three annular parts which are concentric to each other and to the longitudinal axis of the propulsor and by a plurality of linear actuators articulated at their upstream end to the fixed structure of the propulsor. The said annular parts are connected to each other and to the fixed structure of the propulsor by articulation elements and guide devices which permit the joint axial displacement of the three annular parts by the same amount with respect to the fixed structure of the propulsor, as well as a movement of relative rotation of the intermediate and outer annular parts with respect to each other and with respect to the inner annular part, in this way permitting the inclination of the outer annular part in any direction, with center of rotation on a point of the longitudinal axis of the propulsor. The convergent master petals are connected at their upstream end to the inner annular part by cylindrical articulations which are tangential to a theoretical circumference which is concentric to the longitudinal axis of the propulsor and located in a theoretical plane perpendicular to said longitudinal axis of the propulsor. The outer annular part is connected, on its part, by spherical articulations to the downstream end of the said linear actuators. The mechanism for variation of the A8 throat area, in one of the embodiments set forth in said Spanish Patent Application No. 9200369 of 1992, is formed of a lever which is firmly attached to the fixed structure of the propulsor on which there rests and rolls a roller mounted, with possibility of free rotation, on the corresponding convergent master petal. The master petals of the divergent zone are subdivided transversely into two sections which are connected together by a cylindrical articulation the axis of which is perpendicular to the axis of articulation between master petals of the convergent and divergent zones, the downstream section being connected to the outer annular part in said Spanish Patent Application 9200369 (EP-A-557229) by a bar which is connected to said section by a spherical articulation, and to the outer annular part by a cylindrical articulation which is tangential to a theoretical circumference which is concentric to the longitudinal axis of the propulsor and located in a theoretical plane perpendicular to said longitudinal axis of the propulsor. The upstream section of each divergent master petal is connected, at its upstream end, to the corresponding convergent master petal by a cylindrical articulation, tangential to a theoretical circumference which is concentric to the longitudinal axis of the propulsor and located in a theoretical plane perpendicular to said longitudinal axis of the propulsor. Spanish Patent Application No. 9202157 of 1992 describes and claims a design of divergent slave petal for the sealing of the longitudinal space between contiguous divergent master petals. The geometry of said longitudinal spaces between divergent master petals is changed during the orientation of the flow, changing from an approximately rectangular form to that of an adjusted surface the sides of which are no longer parallel. In said Spanish Patent Application No. 9202157 it is proposed to convert every divergent slave petal into a deformable structural unit of minimum stiffness in torsion, formed of a base plate and a plurality of discrete transverse elements inserted in said base plate. This base plate imparts axial stiffness to the unit, serving as element bearing the axial forces due to the flow of gas, the cooling air, and the inertia forces, but presenting minimum ability to transmit transverse forces. On their part, the discrete transverse elements lack ability to transmit torsion and they transmit the transverse forces and the shearing forces imposed both by the flow of gas and by the divergent master petals to which the gas pressure exerted on the base plate bearing the axial forces is transmitted. In this way, with Spanish Patent Applications 9200369 and 9202157 of 1992, we have a mechanism capable of orienting the flow of gas by acting solely on a part of the divergent zone of the nozzle and a suitable sealing of the longitudinal space between contiguous divergent master petals. Spanish Patent Application No. 9301991 of 1993 describes and claims a divergent master petal which makes it possible to increase the maximum angle of orientation of the flow with respect to what it is possible to obtain with the embodiments set forth in Spanish Patent Applications Nos. 9200369 and 9202157. On orienting the divergent zone of the nozzle, the divergent master petals, as described in Spanish Patent Application No. 9200369, are forced to move in radial direction and in tangential direction with respect to the longitudinal axis of the propulsor, the maximum angle of orientation of the divergent zone for a given A8 throat area being limited by the interferences between master and slave petals in zones near the A9 exit area. As indicated previously, Spanish Patent Application 9202157 of 1992 proposes converting the divergent slave petal into a deformable structural unit of minimum stiffness in torsion, formed by a base plate bearing the axial forces and with minimum capacity to transmit transverse forces, and discrete transverse elements with capacity to transmit the transverse forces and the shearing forces imposed both by the flow of gas and by the divergent master petals. If the inner surface, in contact with the flow of gas, of the divergent master petals is flat, the maximum angle of orientation of the flow is determined by the interference in zones close to the A9 exit area of said inner surface with the discrete transverse elements since, in this case, the longitudinal edges of the base plate do not rest on the inner surface of the divergent master petals, a longitudinal opening appearing which permits the passage of the gases to the outside. In order to solve this problem, Spanish Patent Application No. 9301991 proposes a divergent master petal which has an inner surface, in contact with the flow of gas, of a shape variable between two cross sections, one of them straight, coinciding with or close to the upstream end transverse edge of the petal and the other curved, coinciding with or close to the downstream end transverse edge of said petal, the convexity being directed toward the inside of the propulsor. The transmission between the two cross sections is effected gradually and smoothly in order to permit continuous contact of the divergent slave petal with said inner surface. The present invention describes and claims a divergent master petal and a system for connecting it to the outer annular part which makes it possible to increase the maximum angle of orientation of the flow as compared with what it is possible to obtain with the embodiments set forth in Spanish Patent Applications Nos. 9200369, 9202157 and 9301991. Once there is eliminated, upon adopting for the divergent master petal the configuration described in Spanish Patent Application No. 9301991, the problem of interferences in zones close to the A9 exit area between the inner surface of the divergent master petal and the discrete transverse elements which form part of the divergent slave petal described in Spanish Patent Application 9202157, the maximum angle of orientation of the flow is limited by the interferences between each of the divergent master petals or between each of the slave or divergent petals, or else because the divergent slave petal does not rest, in the zone of the A9 exit area, on the corresponding divergent master petals. This happens since in the embodiments set forth in Spanish Patent Application No. 9200369 the downstream section of each divergent master petal is connected to the outer annular part by a single bar which is connected to said section by a spherical articulation and to the outer annular part by a cylindrical articulation, tangential to a theoretical circumference concentric to the longitudinal axis of the propulsor and located in a theoretical plane perpendicular to said longitudinal axis of the propulsor. In this way, the rotation experienced by the outer annular part around a point of the longitudinal axis of the propulsor during the orientation of the flow determines, for each divergent master petal, a movement in radial direction and a movement in tangential direction which are such that, for a selected ratio between the A8 throat area and the A9 exit area, said movements in radial and tangential direction are bi-univocally interrelated, it is not possible to increase the tangential movement of the downstream section of the divergent master petal without appreciably varying its radial movement. In order to solve this problem, the present invention proposes a divergent master petal the downstream section of which is formed by a braced system which is connected to the outer annular part by a connecting system formed of a biarticulated bar connected to both by means of cylindrical articulations which, when there is no orientation of the flow, are tangential to a theoretical circumference concentric to the longitudinal axis of the propulsor and located in a theoretical place perpendicular to said longitudinal axis of the propulsor. The braced system which constitutes the downstream section of the divergent master petal is formed by a stiffened plate the inner surface of which is seen by the flow of gases and which is connected, at its upstream end, to the downstream section of the divergent master petal by a cylindrical articulation the axis of which is perpendicular to the axis of articulation between convergent and divergent master petals, and by two intermediate bars, one located upstream in the direction of flow of the gases with respect to the other, each of them being connected at one end to the stiffened plate by a spherical articulation and, at their other end, connected to each other by a spherical articulation. The downstream section of the divergent master petal thus described is connected to the outer annular part by a biarticulated bar which, at its upstream end, is connected to said outer annular part by a cylindrical articulation which, when there is no orientation of the flow, is tangential to a theoretical circumference concentric to the longitudinal axis of the propulsor and located in a theoretical plane perpendicular to said longitudinal axis of the propulsor, and at its downstream end is articulately connected to the linking end of the two intermediate bars which form part of said downstream section. Said articulated connection is such that the biarticulated bar defines, with the intermediate bar located upstream, a cylindrical articulation which, when there is no orientation of the flow, is tangential to a theoretical circumference concentric to the longitudinal axis of the propulsor and located in a theoretical plane perpendicular to said longitudinal axis of the propulsor and, with the intermediate bar located downstream, a spherical articulation. In this way, the result is obtained that, during the orientation of the flow, the tangential movement experienced by the downstream section of the divergent master petal is defined solely by the biarticulated bar of connection to the outer annular part and by the intermediate bar located upstream, so that, the point of connection of the biarticulated bar and the two intermediate bars being maintained, and modifying the longitudinal position of the spherical articulation which connects the stiffened plate and the tierod located upstream, it is possible to regulate in the most convenient manner the tangential movement of the downstream section of the divergent master petal for a fixed radial movement of it. All the characteristics of the invention, as set forth in the claims, will be better understood from the following description, read with reference to the accompanying drawings, in which one non-limitative embodiment is shown. In the drawings: Fig. 1 is a perspective view, partially in section, of an orientable nozzle developed in accordance with the description given. Fig. 2 is a cross section through the nozzle along the section line AA-AA of Fig. 3, showing the connections between the elements which form the system for the simultaneous control of the A8 throat area and the orientation of the flow. Fig. 3 is a longitudinal section through the nozzle along the section line BB-BB of Fig. 2, showing the nozzle in closed position without orientation of the flow. Fig. 4 is a longitudinal section through the nozzle along the section line CC-CC of Fig. 2, with the nozzle in closed position and without orientation of the flow. Fig. 5 is a longitudinal section through the nozzle along the section line DD-DD of Fig. 2, with the nozzle in closed position, without orientation of the thrust. Figs. 6 and 7 are longitudinal section through the nozzle along the section line DD-DD of Fig. 2, with the nozzle in closed position and open position respectively, in both cases with orientation of the thrust. Fig. 8 is a longitudinal section through the nozzle along the section line EE-EE of Fig. 2, with the nozzle in open position, without orientation of the thrust. Figs. 9 and 10 are rear views of the nozzle, without orientation of the flow and with orientation of the flow respectively. Fig. 11 is a partial perspective view of the arch ? of the divergent zone of the nozzle, formed in accordance with the description given. Fig. 1 shows a schematic perspective view, partially in section, of the nozzle which is the object of the description, the arrow A indicating the direction of flow or circulation of the gases. In the same way as traditional nozzles, the nozzle shown in Fig. 1 includes a rear carcass, indicated by the numeral 1, which constitutes the final end of the fixed structure of the propulsor, a convergent zone, indicated by the numeral 2, and a divergent zone indicated by the numeral 3. The convergent zone 2 is formed of a plurality of master petals designated 4 and slave petals, not shown. In the same way, the divergent zone 3 is formed of master petals 5 and slaves, not shown. The nozzle also includes a control system for the A8 throat area, designated 12 in Fig. 5 and defined by the intersection between the convergent petals 4 and divergent petals 5, and for the orientation of the flow. The variation of the A8 throat area and the orientation of the flow are effected by a single control system which is formed of three annular parts 6, 7 and 8, concentric to each other and to the longitudinal axis 34 of the propulsor, and by a plurality of linear actuators 9 which are articulated at their upstream end to the fixed structure of the propulsor 1. The convergent master petals 4, Figs. 5 to 8, are connected, at their upstream end, to the inner annular part 8. This connection is effected by cylindrical articulations 10 tangential to a theoretical circumference concentric to the longitudinal axis of the propulsor and located in a theoretical plane perpendicular to said longitudinal axis of the propulsor. The downstream ends of the linear actuators 9 are connected to the outer annular part 6 by spherical articulations 11 (Figs. 2 and 8). Furthermore, the outer annular part 6 is connected to the divergent master petals 5 by biarticulated bars 15 which are mounted concentrically around the axis 34 of the propulsor. Each biarticulated bar 15 is connected to the outer annular part 6 by the cylindrical articulation 16, and its connection to the divergent master petal 5 is effected by means of a cylindrical articulation 17 (Figs. 5 to 8 and 11). The two cylindrical articulations, 16 and 17, are so arranged that, without orientation of the flow, they are tangent to a theoretical circumference concentric to the longitudinal axis of the propulsor and located in a theoretical plane perpendicular to said longitudinal axis of the propulsor. The control system of the nozzle includes, furthermore, a mechanism for modifying the A8 throat area, designated by the numeral 12, which mechanism, as shown in Figs. 5 to 8, is formed of a lever 18 which is firmly attached to the fixed structure 1 of the propulsor, on which there rests and rolls a roller 19 mounted, with the possibility of free rotation, on the corresponding convergent master petal. The annular parts 6, 7 and 8 are furthermore connected to each other by devices which permit the axial displacement of the unit consisting of the three parts by an equal amount, with respect to the structure of the propulsor, as well as a movement of relative rotation of the intermediate annular part 7 and the outer annular part 6 between themselves and with respect to the inner annular part 8, so as to permit the inclination of the outer annular part 6 in any direction, with center of rotation on the axis 14 of the propulsor. In this way, the outer annular part 6 and the inner annular part 8 are permitted to carry out between themselves, through the intermediate annular part 7, a relative movement of rotation in space, determining a spherical joint. For this, the annular parts 6 and 7 are connected together by a cylindrical articulation, defined by the shafts 20, Figs. 2 and 3, which are aligned in diametrically opposite position, while the annular parts 7 and 8 are connected to each other by another cylindrical articulation defined by the shafts 21, Figs. 2 and 4, which are also aligned with each other diametrically, in position perpendicular to the shafts 20. In order to reduce the play between the annular parts 6, 7 and 8 and minimize the rubbing between them during their relative rotation, axial thrust bearings, designated 22 in Figs. 2, 3 and 4, are arranged concentrically to the shafts 20 and 21. As can be seen from Figs. 3 to 8, the annular part 8 has a cylindrical extension 8a, by which there is obtained the sealing of the "post-combustor" during the adjustment of the A8 throat area 12 of the nozzle. The axis of this cylindrical extension 8a must be located at all times on the longitudinal axis 14 of the propulsor, for which there will be arranged, on the upstream end of said cylindrical extension 8a, rollers, not shown in the Figures, which will move only in axial direction on the inside of guides integral with the fixed structure 1 of the propulsor in order to define the guide device for the annular part 8, as set forth in Spanish Patent Application No. 9200369. On its part, the annular part 6 is guided by a device formed by the rollers 23, Fig. 2, which can move only in axial direction, within guides integral with the fixed structure 1, with a small amount of play in order to permit the rotation of this annular part 6 around any diameter. The guides of the annular parts 6 and 8 will have to absorb the net shearing forces which appear during the orientation of the flow and those due to asymmetries of the loads. The arrangement described, shown in the figures, permits the following movements by activation in one or the other direction of the linear actuators 9: Axial movement of the assembly of annular parts 6, 7 and 8, together with the biarticulated bars 15, and the petals 4, making it possible to vary the A8 throat area, indicated by 12 in Figs. 5 and 8. The displacement of the annular parts 6, 7 and 8 by the action of the linear actuators 9 causes the radial displacement of the convergent master petals 4 via the articulation 10. Said convergent master petals 4, due to the lever 18 and by means of the roller 19, open or close in radial direction, defining, together with the biarticulated bars 15, the position of the divergent master petals 5. In this case, the linear actuators 9 will always have the same length. Each of the actuators 9 can lengthen or shorten so that the outer annular part 6 is moved over a theoretical spherical surface, centered on the longitudinal axis 14 of the propulsor, the annular part 8 remaining fixed in axial position and there then taking place, through the same mechanisms, the orientation of the flow in any direction around the longitudinal axis 14 of the propulsor. In the actuation indicated, the biarticulated bars 15, which are connected by a cylindrical articulation 16 to the annular part 6, turn with the latter and compel the divergent master petals 5 to move in radial direction, which movement is indicated by the arrow R in Fig. 10, and in tangential direction, which movement is indicated by the arrow T in said Fig. 10, thus making it possible to obtain the orientation of the flow in the direction indicated by the arrow B. For this, the divergent master petal is subdivided into two sections, designated by the numerals 5a and 5b, connected together by a cylindrical articulation 24 arranged in direction perpendicular to the center line of the base of the petal 5, as can be better noted from Figs. 5 to 11. The element or section 5a is connected by a cylindrical articulation 25 to the convergent master petal 4, Figs. 5 to 8. The downstream section 5b of the divergent master petal is formed of a braced system of two intermediate bars 26 and 27, one located upstream with respect to the other, and a stiffened plate 28, the inner surface of which is seen by the flow of gases. The intermediate bar 27 located downstream is connected at one end by a spherical articulation 29 to the stiffened plate 28 and, at its other end, by another spherical articulation 30, to the intermediate bar 26 located upstream. This intermediate bar 26, which is located upstream is, in its turn, connected at one end by a spherical articulation 31 to the stiffened plate 28 while, at its other end, it is connected by a cylindrical articulation 32 to the biarticulated bar 15, on the axis of which cylindrical articulation there is located the spherical articulation 30 which connects the downstream intermediate bar 27 to the upstream intermediate bar 26. In this way, the geometry which defines the tangential movement of the downstream section 5b of the divergent master petals 5, is made independent of the geometry which defines the radial movement of the sections 5a and 5b during the orientations of the flow. In fact, upon rotation of the outer annular part 6, through the biarticulated bar 15 and the intermediate bar 26 located upstream, the section 5b located downstream of the divergent master petal is compelled to experience a tangential movement defined by said bar 15 and the intermediate bar 26 and their respective points of articulation. The radial movements experienced by the divergent petal depends fundamentally on the geometrical position of the articulations 16, 17, 25, 29, 30 and 32, whereby maintaining fixed the geometrical position of said articulations and modifying the geometrical position of the spherical articulation 31 which connects the upstream intermediate bar 26 and the stiffened plate 28, the tangential movement of the section 5b can be increased or decreased during the orientation of the flow, without substantially changing the radial movement of the divergent master petal 5, with and without orientation of the flow, as can be better noted from Figs. 5 to 11. In Fig. 3, the nozzle is shown in closed position without orientation of the flow, while in Fig. 4, the nozzle is shown in open position, also without orientation of the flow. In both Figs. 3 and 4, there are diagrammatically shown the convergent slave petal 33 and divergent slave petal 34 for the sealing of the spaces between master petals 4 and 5. As explained previously, in Spanish Patent Application 9202157 of 1992, a solution is proposed for the divergent slave petal 34 which makes it possible to solve the problem of the space between divergent master petals during the orientation of the flow. The inner surface of the divergent master petal has been shown in Figs. 1 and 5 to 11 as it is proposed in Spanish Patent Application No. 9301991 of 1993, that is to say with a form variable between two cross sections, one of them straight and located close to the upstream transverse edge of the divergent master petal 5 and the over curved, close to the downstream end transverse edge of the petal 5 and with its convexity directed towards the longitudinal axis 14 of the propulsor. In Fig. 5 the nozzle is shown in closed position without orientation of the flow, there being shown a longitudinal section thereof through the master petals, in the same way as in Fig. 6 in which the nozzle is shown in closed position and orienting the flow; and Fig. 7 shows the nozzle in open position, orienting the flow. Fig. 8 shows the nozzle in open position without orientation of the flow. Figs. 9 and 10 are rear views of the nozzle, with and without orientation of the flow, in order to illustrate the radial and tangential movements experienced by the divergent master petals 5. Fig. 11 provides a perspective view of the mechanism forming the object of the present invention, together with the two lugs which prevent the rotary movement of the intermediate bar 27 around the theoretical axis which passes through the centers of the spherical joints 29 and 30. For reasons of clarity, there have not been shown in Figs. 5 to 8 and 11 the moving elements 35 and 36 which constitute the movable cover of the nozzle around the divergent section, similar to those described in Spanish Patent Application No. 9200369 of 1992. Said movable elements 35 and 36 are shown in Figs. 1, 3 and 4 only. It is clear that the mechanism described in the present application is applicable to any type of axisymmetric nozzle orientable in its divergent zone and of variable geometry such that, in order to orient the flow, it has an outer annular part 6, regardless of whether the variation of the A8 throat area 12 and the orientation of the flow is effected by a single control system or by two independent control systems. Furthermore, the mechanism described is applicable to a divergent master petal 5 formed of a single section instead of the two sections 5a and 5b shown in the figures and connected to the corresponding convergent master petal by means of a spherical joint instead of the cylindrical articulation 25 shown in the figures. The features described make it possible to make the geometry defining the radial movement of convergent and divergent master and slave petals 4 and 5 independent of the geometry which defines the tangential movement of the divergent master petals 5 and, by means thereof, of the divergent slaves 34, so that, for a given law of variation of the A8 exit area 12, the tangential movement of the downstream sections 5b of the divergent master petals can be increased or decreased, in order to increase the range of A8 throat areas 12 in which it is possible to orient the flow a given angle.

Claims: An orientable axisymmetric nozzle of variable geometry for gas turbine propulsors, which comprises a convergent section (2) followed, in the direction of flow, by a divergent section (3), both formed by master petals (4, 5) connected together by articulations and by slave petals (33, 34), also connected together by articulations, both of them being distributed circumferentially around the longitudinal axis (14) of the propulsor; the convergent section (2) defining an A8 variable area throat (12) and the divergent section (3) being of variable geometry in order to orient the flow in any direction on a cone located around the longitudinal axis (14) of the propulsor, including control means for regulating the A8 throat area (12) and control means for orienting the flow, by the axial displacement and the inclination of an outer annular part (6) in any direction, with center of rotation on a point of the longitudinal axis (14) of the propulsor respectively, each divergent master petal (5) being connected to the outer annular part (6) by a biarticulated bar (15), connected directly by one of its ends to the outer annular part (6) by a cylindrical articulation (16) which, when there is no orientation of the flow, is tangent to a theoretical circumference concentric to the longitudinal axis (14) of the propulsor and located in a theoretical plane perpendicular to said longitudinal axis (14) of the propulsor, characterized by the fact that the biarticulated bar (15) while by the opposite end it is connected via two intermediate bars (26, 27) to the divergent master petal; which intermediate bars (26, 27) are connected by one of their ends to the divergent master petal (5) at longitudinally aligned points of said petal by spherical articulations (29, 31) and are connected together by a spherical articulation (30), the intermediate bar (26) which is upstream being furthermore connected to the biarticulated bar (15) by a cylindrical articulation (32) with axis (17) which, when there is no orientation of the flow, is tangent to a theoretical circumference concentric to the longitudinal axis (14) of the propulsor and located in a theoretical plane perpendicular to said longitudinal axis (14) of the propulsor. A nozzle according to Claim 1, in which every divergent master petal is formed by a single section and connected by its upstream end to the corresponding convergent master petal (4) by means of a spherical articulation, characterized by the fact that the said petal is formed by a stiffened plate the inner surface of which is licked by the gases and to the outer surface of which the intermediate bars (26, 27) are connected by spherical articulations (31, 29). A nozzle according to Claim 1, in which every divergent master petal is formed of two sections (5a, 5b) which are connected together by a cylindrical articulation (24) the axis of which is perpendicular to the axis (25) of articulation between master petals (4 and 5), said articulation (25) being cylindrical and tangential to a theoretical circumference concentric to the longitudinal axis (14) of the propulsor and located in a theoretical plane perpendicular to said longitudinal axis (14) of the propulsor, characterized by the fact that the downstream section (5b) is formed by stiffened plate the inner surface of which is licked by the gases and to the outer surface of which the intermediate bars (26, 27) are connected by spherical articulations (31, 29). A nozzle according to Claim 2 or 3, characterized by the fact that the spherical articulation (30) which connects the intermediate bar (27) located downstream with the intermediate bar (26) located upstream is located on the axis of the cylindrical articulation (17, 32) which connects the biarticulated bar (15) with the intermediate bar (26) located upstream. A nozzle according to Claim 2 or 3, characterized by the fact that the connection between the downstream intermediate bar (27) and the divergent master petal (5) has lateral stops (37) which prevent the rotation of said intermediate bar (27) around the axis which passes through its end spherical articulations (29, 30).

Inventors: RIVACOBA URRUELA JOSE, RIVACOBA URRUELA, JOSE
Applicants: SENER ING & SIST, SENER, INGENIERIA Y SISTEMAS, S.A.
Application year: 1994
Main classification: F02K1
IPC codes: F02K1